This invention relates to thrust and journal bearings for rotating shafts, and particularly to foil bearings for supporting such shafts on self-acting or externally pressurized air bearing films.
Hard (e.g., solid metal) thrust and journal bearings for rotating shafts are known in the art, and have been adapted for the production of self-acting or externally pressurized air bearing films. However, such hard bearings are apt to suffer great damage, or even to be destroyed, if a particle of foreign matter, particularly very hard matter, gets into the air bearing film zone.
Foil journal bearings of the sling type, i.e., wrapped at least part way around the shaft, have also been used with self-acting air bearing films, and are well adapted to tolerate foreign particles without damage, but are conversely inclined to be somewhat more yielding to bodily displacement of the shaft itself than is desirable in some applications, for example, applications in which the precise maintenance of a certain axial position is required for the rotating shaft.